[PATCH 08/17] libfs: simple_transaction_get(): replace get_zeroed_page() with kzalloc()

[Mike Rapoport (Microsoft)]

simple_transaction_get() allocates memory with get_zeroed_page(). That
memory is used as a file local buffer that is accessed using
copy_from_user() and simple_read_from_buffer().

kmalloc() is a better API for such use and it also provides better
scalability and more debugging possibilities.

Replace use of get_zeroed_page() with kzalloc().

Signed-off-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
---
 fs/libfs.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/libfs.c b/fs/libfs.c
index 1bbea5e7bae3..80a330c8296f 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -1258,7 +1258,7 @@ char *simple_transaction_get(struct file *file, const char __user *buf, size_t s
 	if (size > SIMPLE_TRANSACTION_LIMIT - 1)
 		return ERR_PTR(-EFBIG);
 
-	ar = (struct simple_transaction_argresp *)get_zeroed_page(GFP_KERNEL);
+	ar = kzalloc(PAGE_SIZE, GFP_KERNEL);
 	if (!ar)
 		return ERR_PTR(-ENOMEM);
 
@@ -1267,7 +1267,7 @@ char *simple_transaction_get(struct file *file, const char __user *buf, size_t s
 	/* only one write allowed per open */
 	if (file->private_data) {
 		spin_unlock(&simple_transaction_lock);
-		free_page((unsigned long)ar);
+		kfree(ar);
 		return ERR_PTR(-EBUSY);
 	}
 
@@ -1294,7 +1294,7 @@ EXPORT_SYMBOL(simple_transaction_read);
 
 int simple_transaction_release(struct inode *inode, struct file *file)
 {
-	free_page((unsigned long)file->private_data);
+	kfree(file->private_data);
 	return 0;
 }
 EXPORT_SYMBOL(simple_transaction_release);

-- 
2.53.0